Improvement in



UNITED STATES PATENT OFFICE.

OSCAR MAYO, OF EVANSTON, ILLINOIS.

IMPROVEMENT IN TREATING PAPER TO liENDER lT INCOMBUSTIBLE.

Specification forming part of Letters Patent No. 199,656, dated January 29, 1878; application filed January 4, 1878.

To all whom it may concern:

Be it known that I, OSCAR MAYO, of the town of Evanston, in the county of Cook and State of Illinois, have invented anew and useful Process of Preparing Paper, so as to per, and subject same to two baths, drying. same after each-namely, the first a strong solution of salt, and the other a full solution of the phosphate and tun gstate of soda, in equal parts.

I claim- The process of rendering paper infusible and comparatively inoombustible, by subjecting same to a bath of a strong solution of salt, and, after drying, to a bath of the solution, of equal parts, of the phosphate and the tungstate of soda, substantially as described.

OSCAR MAYO.

Witnesses:

PERCY B. MARLING, D. G. STUART. 

